Hydrobromination of alpha-olefins with prior air-blowing

ABSTRACT

A method is provided for the uniform activation of substantially pure alpha-olefins such as those prepared by the ethylene buildup procedure using catalysts such as Al(Et)3. The olefin is activated by air-blowing at a temperature from 60* to 200* C. The activated olefin is thereafter reacted with anhydrous HBr to produce the desired primary alkyl bromide in the absence of an extraneously added catalyst at a temperature less than 50* C.

United States Patent Hay et a1.

[54] HYDROBROMINATION OF ALPHA- OLEFINS WITH PRIOR AIR-BLOWINGInventors: Russell G. Hay, Gibsonia; Clarence R. Murphy, Allison Park;William L. Walsh, Glenshaw, all of Pa.

Gull Research 8: Development Company, Pittsburgh, Pa.

Filed: Sept. 9, 1969 Appl. No.: 856,374

Assignee:

11.8. CI ..260/663 Int. Cl ..C07c 17/08 Field of Search ..260/663,683.15 D

[56] References Cited UNITED STATES PATENTS 3,422,145 1/1969 Steinmetz..260/663 3,683,037 Aug. 8, 1972 3,482,000 12/1969 Fernald etal.....260/683. 15 D 3,471,562 10/ 1969 Wakeman et a1 ..260/6633,546,306 10/ l 970 McCarthy ..260/663 Primary Examiner-Daniel D.Horwitz Attorney-Meyer Neishloss, Deane E. Keith and Richard C. Gaffney[57] ABSTRACT A method is provided for the uniform activation ofsubstantially pure alpha-olefins such as those prepared by the ethylenebuild-up procedure using catalysts such as Al(Et);,. The olefin isactivated by air-blowing at a temperature from 60 to 200 C. Theactivated olefin is thereafter reacted with anhydrous l-lBr to producethe desired primary alkyl bromide in the absence of an extraneouslyadded catalyst at a temperature less than 50 C.

10 Claims, 1 lh'awing Figure TIME HOURS OPERATIVE REGION INOPERATIVEREGION E5 INOPERATIVE REGION TEMPERATURE C PAIENTEIIIIII; a IIIz3.683.037

FIG. I

IOOO

" INOPERATIVE REGION IOO E (n CC 8 OPERATIVE I REGION m 55 g I: I:

o. E INOPERATIVE I REGION 0 i l I 60 80 |OO I I40 200 TEMPERATURE CINVENTORS RUSSELL HAY I BY CLARENCE R. MURPHY WILLIAM L. WALSH Thisinvention relates to the preparation of primary alkyl bromides by thereaction of anhydrous HBr with a substantially pure alpha-olefin.

The addition of HBr to alpha-olefins to produce primary and secondarybromides is known. It is also known that primary alkyl bromides can bemade by the addition of HBr to alpha-olefins in the simultaneouspresence of free radical promoters, such as ultraviolet light (US. Pat.No. 2,307,532); extraneously added peroxides, such as organic peroxides(US. Pat. No. 2,058,466 and British Pat. No. 843,234); or air (US. Pat.No. 3,108,141). Other prior art appears to be contradictory (U.S. Pat.No. 3,336,403) in teaching the use of peroxidas is undesirable due topolymerization problems and further that the use of oxygen or airsimultaneously with HBr is slow. Indeed, it has been found that in someinstances the hydrobromination of alpha-olefins proceeded rapidly whenair and HBr were simultaneously added while in other instances thereaction was unexplicably slow. It was found, however, that for asubstantially pure olefin, that is, an olefin which contains nodetectable amount of oxygen containing materials of any type, thereaction with HBr in the simultaneous presence of air was uniformlyslow, thus the general teachings in US. Pat. 3,336,403. The simultaneousaddition of air and HBr must be conducted at a temperature less thanabout 50 C., even in the presence of free radical promoters, ifsubstantial amounts of secondary alkyl bromides are to be avoided. Thus,it was not possible to increase the temperature of the hydrobrominationreaction in the simultaneous presence of air in order to speed up theslow reaction since, in so doing, substantial amounts of undesirablesecondary bromides would result. It is for this reason that the priorart teaches the use of low tem perature olefin activation, such asultraviolet light; the addition of extraneous peroxides, such as organicperoxide; or the priorformation of ozonides. All of these methods sufferfrom the difficulty that they are expensive and not easily controlled.

A procedure to insure the uniform activation of a substantially purealpha-olefin has now been found which is simple, easy to control,inexpensive and allows for the production of high yields of primaryalkyl bromides without the need for an extraneously added free a radicalpromoter.

in accordance with the invention, a primary alkyl bromide is preparedfrom a substantially pure alphaolefin having from four to 30 carbonatoms by a process which comprises:

contacting at least one of said alpha-olefins with a gas containing freemolecular oxygen at a temperature from about:60 to 200 C. for a timesuflicient to result in activation of said olefin; and

thereafter reacting said alpha-olefin with anhydrous HBr in the absenceof an exu'aneously added catalyst at a temperature less than 50 C. toproduce the desired alkyl bromide.

In one preferred embodiment of this invention the alpha-olefin chargestock is prepared by the telomerization of ethylene under telomerizationconditions in the presence of a Group IIIA metal alkyl.

Unexpectedly, it was found that the substantially pure olefins could beactivated by air-blowing at a temperature exceeding the normalhydrobromination reaction temperature in reasonable time periods withoutthe subsequent formation of the unwanted sec-alkyl bromides.

The alpha-olefin charge stock can be any substantially pure alpha-olefinhaving from four to 30 carbon atoms per molecule and is preferably analpha-olefm having from four to ten carbon atoms per molecule. Thealpha-olefin can suitably have the formula:

Examples of suitable alpha-olefins include, but are not limited to:

butene-l; pentene-l;

isobutylene; hexenel; 3-methylbutene-l; 4-ethylhexenel; ocetene-l;dodecene-l;

decenel; octadeccne-l; tetradecene-l; Z-methyll -nonadecene; eicosene-l;tetracosene-l;

2-octyl-l-dodecene; and mixtures thereof.

While any of the above alpha-olefins can be used in the process of thisinvention to insure the production of primary alkyl bromides without theneed of an extroneously added free radical catalyst, the process of thisinvention is particularly applicable to the hydrobromination ofsubstantially pure alpha-olefins. By substantially pure alpha-olefins ismeant those alpha-olefins which are prepared by the telomerization of alow molecular weight olefin having from two to six carbon atoms permolecule, such as ethylene, under telomerization conditions in thepresence of a catalyst such as a Group IIlA metal alkyl such as definedbelow, for example, aluminum triethyl. Very pure olefins must be used inthe telomerization process since the Group IIIA metal alkyls act asscavengers for any oxygen containing materials which might be presentand reduce the efficiency of the telomerization reaction. Thus, thetelomerization products which are obtained are substantially unreactivein the hydrobromination reaction as defined above. For example, thealpha-olefins freshly produced by the telomerization process result in ayield of less than 50 mole percent, usually less than ten mole percent,primary alkyl bromide when reacted with anhydrous hydrogen bromide inthe absence of an extraneously added catalyst at 1 0 to 0 C. in a timeof about two hours. Yet another way to obtain the substantially purealpha-olefins would be, of course, to distill the alpha-olefins in thecontact presence of a Group IIIA metal alkyl having at least one metalto carbon bond. By a Group IIIA metal is meant boron, aluminum, galium,indium and tellurium. By a metal alkyl is meant a metal alkyl whereinthere is at least one metal to carbon bond, the carbon being a portionof an alkyl group. The metal alkyls can suitably have the formula:

where Me is any of the Group lIIA metals defined above and wherein atleast one and preferably all of R R and R are alkyl radicals havingbetween one and ten carbon atoms and wherein any one or two of R R and Rcan be selected from the group consisting of hydrogen and halogenradicals. Usually the metal alkyl is an aluminum or boron trialkyl suchas triisobutylaluminum or triisobutylboron.

As noted, the substantially pure alpha-olefms prepared as above werefound to be substantially inactive for the addition of l-lBr in theabsence of an extraneously added free radical promoter. The simultaneousaddition of oxygen in the form of air with the HBr to the alpha-olefinsproved to be a very slow reaction requiring more than six hours at 28 C.to produce any appreciable amount of product.

It was found that the olefins could be simply and effectively activatedby pretreatment before the HBr addition, the pretreatment consisting ofcontacting the alpha-olefin charge stock with a gas containing freemolecular oxygen at a temperature between 60 C. and 200 C. for a timesufficient to activate the alphaolefins. By an activated olefin is meantone which results in a yield of at least 85 mole percent primary alkylbromide when reacted with anhydrous hydrogen bromide in the absence ofan extraneously added catalyst at l to 0 C. in a reaction time of lessthan minutes. Attempts were made to determine the peroxide number of theactivated olefins and correlate activity with peroxide number, but suchattempts failed since the peroxide numbers were inconsistent and activeolefins had a peroxide number level so low that it was beyond the scopeof the method. At temperatures below 60C. the time required to activatethe alphaolefins is undesirably long. At temperatures above 200 C. thetime is undesirably short. It has also been found that if the time atany given temperature is too long, then, for some unknown reason, thealpha-olefin is inoperable for the hydrobromination reaction either withor without the addition of an extraneously added free radical promoter.Thus, it has been found that the time and the temperature must becarefully correlated to result in an olefin which is active for thehydrobromination without the need for an extraneously added free radicalpromoter. Times as short as 1 minute or less are effective at the highertemperatures whereas times on the order of 6 hours are required at thelower temperatures. FIG. 1 attached is a plot on a semi-log scale of thetime required vs. temperature to obtain an olefin in the OperativeRegion which is the region where an olefin would be active for thehydrobromination reaction without the need for an extraneously addedfree radical catalyst. The time in hours is on a semi-log scale. Thus,referring to FIG. 1, at 70 C. a minimum of 6 hours would be required toactivate the alpha-olefin whereas at 170 C. about one minute isrequired. At 170 C., however, activation for more than l- 1; hours willresult in an olefin which is inoperative in the process of thisinvention. Similarly, at 120 C. an activation time can be from about 3minutes to about 11 hours, while at 200 C. the activation time is fromabout 0.5 seconds to about 36 minutes. It can easily be seen from FIG. 1that the minimum activation times can vary over a wide range of severalseconds at 200 C. to about 50 hours at C. Since the hydrobrominationreaction must be run at less than 60 C. to avoid the formation ofundesired secondary bromides, it is quite apparent that the simultaneousaddition of HBr and air to a substantially pure olefin would be so slowas to be considered unreactive. These conclusions have beensubstantiated experimentally.

The activation of the substantially pure alpha-olefins occurs quitesimply by passage of a gas containing free molecular oxygen through theliquid alpha-olefin at the desired activation temperature. The termair-blown or air-blowing in this application refers to blowing with agas containing free molecular oxygen which may be, but is notnecessarily, air. Means should be provided for insuring intimate contactbetween the gas containing free molecular oxygen and liquid olefins tobe activated. For example, the gas containing free molecular oxygen canbe added to the liquid olefin through a sparger system which breaks upthe gas into very small bubbles. While additional stirring is notrequired, it can be employed if desired. The gas containing freemolecular oxygen can suitably be air, pure oxygen, or molecular oxygendiluted with an inert gas such as nitrogen. The gas suitably containsfrom 15 to mole percent free molecular oxygen, and preferably from 15 to40 mole percent free molecular oxygen. Amounts of oxygen in theactivating gas less than about five mole percent would merely prolongthe contact times necessary for activation as shown on FIG. 1. Thepreferred activating gas is, of course, air.

One of the factors to be considered in determining the proper activationtemperature is, of course, the boiling point of the olefin charge stock.It is necessary for economic reasons to activate the olefin in theliquid phase, but it is also obvious that as the activation temperatureincreases the olefins tend to volatilize and some form of pressureequipment would be required in many instances to maintain the olefins inthe liquid phase when using the higher activation temperatures. Thus,for the lower molecular weight olefins such as butenes and pentenes, itis necessary to utilize the lower activation temperatures which requiremore activation time in order to avoid the expense of resorting to highpressure equipment. For the higher molecular weight olefinic chargestocks which remain liquid even at the higher activation temperatureranges, it is possible, due to the unexpectedly short activation timesrequired, to activate said olefinic charge stocks in the transfer linebetween the olefin production units or storage tank and thehydrobromination reactor, provided, of course, means are available forthe intimate contacting of the olefinic charge stock in the transferline with a gas containing free molecular oxygen. For purposes of bettercontrol, however, it is preferred that the activation temperature forall olefins be between 60 C. and 170 C., and more preferably between 70C. and C., for the olefins which are liquid at normal pressures in thistemperature range. The activated olefin can then be charged to ahydrobromination reactor where it is contacted with anhydrous hydrogenbromide gas. The presence of moisture in the system in small quantitiesof about 1 percent or less is not harmful to the reaction, but moistureshould be avoided as it may be harmful to the reaction equipment. Thehydrogen bromide can be obtained from any suitable source, and how it isprepared or from whence it comes is not critical to the process of thesubject invention.

The gaseous hydrogen bromide adds to the activated alpha-olefins in ananti-Markownikoff manner. Markownikoff stated in 1870 that if anunsymmetrical olefin is treated with hydrogen halide the addition willoccur at the carbon-carbon double bond and that the hydrogen will attachitself to the carbon atom bearing the greater number of hydrogen atomsand that the halide would attach itself to the carbon atom bearing theleast number of hydrogen atoms. Thus the normal or Markownikoff additionwould produce a secondary alkyl bromide whereas the anti-Markownikoffaddition produces the more desirable abnormal or anti-Man kownikoffprimary alkyl bromide.

The hydrogen bromide addition reaction occurs rapidly in any reactorproviding for good mass transfer between the gaseous hydrogen bromidephase and the liquid alpha-olefin phase. For example, suitable masstransfer conditions for the addition of the hydrogen bromide to theolefin are obtained by bubbling the hydrogen bromide gas through theliquid activated olefin using, for example, a porous plate gasdistributor to insure small gas bubbles resulting in a large interphasearea. It is also preferred, of course, to provide vigorous agitation ofthe liquid phase to aid in the mass transfer and also to insure themaintenance of the desirable low reaction temperatures to be definedbelow. Under the excellent mass transfer conditions, the reaction isover in a matter of minutes even employing the low reaction temperaturesto be defined below.

A suitable range of reaction temperatures is from -30 to 50 C., with thepreferred reaction temperatures between l C. and 30 C. The use ofincreased reaction temperatures is undesirable as the highertemperatures promote the normal or Markownikofi addition with theconsequent formation of the less desirable, less stable secondary alkylbromides. When the reaction is operated in the defined temperaturerange, rapid completion of the hydrogen bromide addition occurs with thesuppression of the formation of secondary alkyl bromides. Thus, suitablereaction times are between 1 and 240 minutes, and in the preferredtemperature range the reaction times are usually between 3 and 120minutes.

The reaction pressure can suitably be between atmospheric and 100 psigor more. An increase in reaction pressure tends to increase the reactionrate. However, since the reaction rate is already quite fast atatmospheric pressure, the use of increased reaction pressures, whiletechnically feasible, is not preferred for obvious economic reasons.

The hydrobromination reaction product which is composed predominantly ofprimary alkyl bromides and small amounts of secondary alkyl bromides isusually purged of excess hydrogen bromide in any suitable manner. Forexample, nitrogen or helium can be passed or bubbled through thereaction product until free of hydrogen bromide. The resulting hydrogenbromide free alkyl bromide reaction product can then, optionally, beneutralized using any suitable basic solution, for example, a 5 percentaqueous solution of sodium bicarbonate is satisfactory and produces anupper organic phase and a lower aqueous phase. For some applications,for example, esterification reactions, neutralization is not requirednor desired. The upper organic phase containing the alkyl bromides canthen be separated and the alkyl bromide recovered in any suitablemanner.

The crude alkyl bromide reaction product can also be recovered bypurging with a non-reactive gas as described above and thereafterdissolving the alkyl bromide in about one to about ten times its volumeof a non-reactive solvent for the alkyl bromide, such as chloroform orpetroleum ether. The solution of the alkyl bromide in the solvent isthen neutralized as before with a weakly basic solution. Alternatively,the unneutralized solution of the alkyl bromide in the nonreactivesolvent can be washed with water until neutral, and this procedure ispreferred in the case of the more labile alkyl bromides. Whichevermethod is chosen to neutralize, the neutralized solution is then driedin any conventional manner, such as by drying over magnesium sulfate.The solvent can then be removed by evaporation or distillation underreduced pressure. The pure alkyl bromide reaction product can then bedistilled from the dried solvent-free organic phase. The invention willbe further described with reference to the following experimental work.

Octene-l which was prepared by the telomerization of ethylene, wasdistilled from tri-n-butylaluminum in a nitrogen atmosphere to produce asubstantially pure octene-l. The peroxide number of the distilledoctenel was less than 0.1, the limit of ASTM Test 1832.

A series of runs were made wherein the distilled octene-l was air-blownat varying temperatures for varying times. The air-blown olefins werethen contacted with anhydrous hydrogen bromide in the absence of anextraneously added catalyst at a temperature of 1 0 to 0 C. for varyingtimes. The results of this series of runs are shown in Table I below.

Referring to Table 1 below, it can be seen that only the conditions ofair-blowing in Example 3 gave an acceptable mole percent yield ofprimary alkyl bromide in a short length TABLE I of time. Note that fromExample 1 a substantially pure olefin is one which results in a yieldless than 10 mole percent primary alkyl bromide when reacted withanhydrous hydrogen bromide in the absence of an extraneously addedcatalyst at 10 to 0 C. in a time of about 2 hours. An active olefinwould be one which gives at least an 85 mole percent yield of primaryalkyl bromide when reacted with anhydrous hydrogen bromide in theabsence of an extraneously added catalyst at l to 0 C. in a reactiontime of less than 15 minutes. In this application, yield means theconversion of the olefin times the efficiency of conversion of theolefin to the desired primary alkyl bromide.

Another series of runs was made using substantially pure decene-l toinvestigate the use of still higher temperatures for activating thedecene-l for hydrobromination. The decene-l was prepared by thetelomerization of ethylene and was distilled over tri-nbutylaluminum ina nitrogen atmosphere to obtain decene-l which would be similar to freshproduct obtained from a commercial plant producing alphaolefms by thetelomerization of ethylene using a metal alkyl catalyst such astriethylaluminum.

Air was blown through the decene-l for varying times and temperaturesand the air-blown decene-l was then reacted with anhydrous hydrogenbromide at -10 to 0 C. for varying lengths of time by bubbling thehydrogen bromide through the cooled air-blown olefin. The results ofthis series of runs are shown in Table II below.

TABLE II Activation of Alpha-Olefins for Hydrobromination by Air-BlowingDecene-l Examples air-blowing conditions Hydrobromination Data Example 6shows that when no air-blowing is employed, only a 1.5 percent yield ofprimary alkyl bromide is obtained after a 45 minute reaction time at 10to 0 C. Example 10 shows that at 90 C., a 60 minute air-blowing issufficient to activate the olefin for the hydrobromination reactionsince a yield of primary alkyl bromide of 94.6 is obtained in 4-55minutes. Examples 7-9 show that at the higher air-blowing temperaturesof 128 to 170 C. times of 1 to 3 minutes are sufficient to result inactivation of the olefin for the hydrobromination reaction.

The experiments in Table H were performed by charging the decene-1(l50milliliters) to a 500 milliliter three-neck flask equipped with astirrer, thermometer and a gas inlet tube. The flask was cooled to 0 to5 C. with a dry ice acetone bath. The hydrogen bromide was introducedthrough a gas inlet tube. The hydrogen bromide consumption could bechecked by the difference between the inlet and outlet gas bubbles.

Another series of runs were made wherein decene-l was maintained at 170C. and a slow stream of air was passed through so that the liquid wassaturated with air. Samples (about 150 ml.) were taken at specific timeintervals and the samples reacted with anhydrous hydrogen bromide at l0to 0 C. to determine the relative reactivity with hydrogen bromide. Theresults are shown in Table III below.

TABLE III Air-Blowing of Dcene-l which was followed by hydrobrominationof the treated Decene-l Referring to Table III, the results indicatethat the reaction of decene-l with air at 170 C. for 1 hour does notdecrease the yield of primary decyl bromide. However, starting at thesecond hour of reaction with air, the yield of primary decyl bromide isreduced from 2% weight percent to 75.2 weight percent. At the 4 hourpoint, a 53.7 weight percent yield required 10 minutes instead of 3minutes. The reaction with air caused the reaction time to increase to30 minutes. These results in Table III indicate that althoughair-blowing is desirable, the reaction of decene-I with air at 170 C.for more than 1 hour is undesirable.

The results observed in Table III were quite unexpected. Once it wasdiscovered that a substantially pure olefin could be activate by asimple air-blowing treatment, it was quite unexpected to find that theair-blowing treatment also causes deactivation of the olefin if tooprolonged. Thus, the results in Tables I through 1H show that there arecertain critical minimum reaction temperatures and times and certaincritical maximum temperatures and times to obtain an olefin which isactive for the hydrobromination reaction without the need for theaddition of an extraneously added catalyst.

Yet another series of runs was made wherein decenc- 1 was distilled from2.5 weight percent tri-n-butylaluminum in order to obtain an olefinwhich is similar to the olefin product obtained directly from acommercial unit producing olef'ms by the telomerization of ethyleneusing a metal alkyl catalyst such as triethylaluminum. The decene-l wasmaintained a C. and a slow stream of air was passed through so that theliquid was saturated with air. Samples (about ml.) were taken atspecific time intervals and the samples reacted with anhydrous hydrogenbromide at -l0 to 0 C. to determine the relative activity with hydrogenbromide in a manner similar to the experiments in Example 14 above. Thedata from these samples are recorded in Table IV below.

Referring to Table IV below, it can be seen that in about 15 minutes theolefin is activated (compare Examples 22 and 24) while in 15 hours ofair-blowing time, the yield of primary decyl bromide is greatly 9 10decreased (see Example 28) and the yield of secondary gas containingfree molecular oxygen at a temdecyl bromide increased. perature fromabout 60 to 200 C. for a time sufficient to result in activation of saidolefin; and

TABLE V. thereafter reacting said alpha-olefin with anhydrous HBr in theabsence of an extraneously added u G catalyst at a temperature less than50 C. to reac on me air-blowing conditions primary CI of Hydroproducethe deslred pnmary alkyl bronlldes' Ex. Time Temp. Bl yield bromination2. A process for the preparation of a primary alkyl (Mmu'es) bromidefrom a substantially pure alpha-olefin having 22 0.0 5.5 301) from fourto 30 carbon atoms per molecule which com- 2325 110 97.5 i 3 L0 0 983 35contacting at least one of said alpha-olefins with a 25 3.0 110 98.2 5.0gas containing free molecular oxygen under condig tions including atemperature from 60 to 200 C. 27 9.0 110 95.8 l5 and a time from oneminute to 500 hours;

6.0 28 1 50 no (365 Pi thereafter reacting said alpha olefin withanhydrous 50.0 Sec. Br) 30.0 HBr in the absence of an extraneouss added29 1&0 110 893 Sea catalyst at a temperature less than 5 C. to 33- 0 no86 3 S B produce the desired primary alkyl bromide; 30 the time andtemperature in said activation step being such that the yield of primaryalkyl bromide in said addition step is over 85 mole percent.

When the last series of runs was repeated except the A Pmcess accordingto m 1 wherein Said h air-blowing temperature was 70 C., an airolefin isone which has been intimately contacted with time of about 500 hours wasrequired before the acroup HIA meta-l alkyl having atleast one carbon todecene-l was rendered unreactive. metal bond- The above examplesillustrate the two step process of A Process accordmg to fl 1 whefem thethis invention where, in the first stage, the olefin is conandtemperature commons for 531d contactmg tacted with a gas containing freemolecular oxygen at a are within the oPerafive w in temperature between60C. and 200C. for a time suffi- A Process accordance claim 1 wileremthe cient to render the olefin active for the hydrobrominasubstantlauyPure alphaolefin Produced tion reaction. In the second stage theactivated olefin is telqmergzmg ethylene under telomel'lzatloflcondicontacted with anhydrous hydrogen bromide which the Presence of aGroup mA metal alkyl adds in an anti-Markownikofl' fashion to producethe P atelomef Product; and

desired primary alkyl bromides. It is necessary to keep 35 P f 531dtelomer P at least one air out of the second stage reaction as much aspossible olefin havmg to 9 carbon because the presence of air in thesecond stage results A Process accordmg to claim 5 wherem the exact inoxidation of the hydrogen bromide to bromine which m temPeraFm'ecofdifions for said activation are can, in turn, cause the formation ofalkyl dibrornides wlthm the Opemuve Regon as Show the and thus reducethe yield of desirable components. 40

Process according to f wherein the gas Resort may be had to suchvariations and modificacommnmg free moleclflal' W8?" 15 tions as fallwithin the spirit of the invention and the Wig alcordmg 61mm 7 Wheremthe alphad d 1 0 is oc e- 25: g i e c alms 9. A process according toclaim 7 wherein the alphal. A process for preparing a primary alkylbromide olefin decenelfrom asubstantially pure alpha-olefin having fromfour A P 'P acqordmg to clan 5 wherem Said to 30 carbon atoms permolecule which comprises: meta-l alkyl alummlm alkylcontacting at leastone of said alpha-olefms with a Patent No. ,037 Dated August 8, 1972Inventor) Russell Hay Clarence Murphy and William L. Wales? It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Col. 9, Table IV should read:

TABLE IV AirBlowing Conditions Primary C 0 Reaction Time of Ex. TimeTemperature Br Yiel Hydrobromination No. Hours C (Wt.%) (Minutes) (50.0Sec.Br

29 18.0 110 89.3 Sec.Br 30.0

3O 21 O 110 86 Sec .Br 30 O Signed and sealed this 30th day of January1973.

(SEAL) Attest.

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof. Patents

2. A process for the preparation of a primary alkyl bromide from asubstantially pure alpha-olefin having from four to 30 carbon atoms permolecule which comprises: contacting at least one of said alpha-olefinswith a gas containing free molecular oxygen unDer conditions including atemperature from 60* to 200* C. and a time from one minute to 500 hours;thereafter reacting said alpha-olefin with anhydrous HBr in the absenceof an extraneously added catalyst at a temperature less than 50* C. toproduce the desired primary alkyl bromide; the time and temperature insaid activation step being such that the yield of primary alkyl bromidein said addition step is over 85 mole percent.
 3. A process according toclaim 1 wherein said alpha-olefin is one which has been intimatelycontacted with a Group IIIA metal alkyl having at least one carbon tometal bond.
 4. A process according to claim 1 wherein the exact time andtemperature conditions for said contacting are within the OperativeRegion as shown in FIG.
 1. 5. A process in accordance with claim 1wherein the substantially pure alpha-olefin is produced by: telomerizingethylene under telomerization conditions in the presence of a Group IIIAmetal alkyl to produce a telomer product; and separating from saidtelomer product at least one olefin having from four to 30 carbon atoms.6. A process according to claim 5 wherein the exact time and temperatureconditions for said activation are within the Operative Region as shownon the FIG.
 1. 7. A process according to claim 6 wherein the gascontaining free molecular oxygen is air.
 8. A process according to claim7 wherein the alpha-olefin is octene-1.
 9. A process according to claim7 wherein the alpha-olefin is decene-1.
 10. A process according to claim5 wherein said metal alkyl is an aluminum alkyl.